Issue #2545972 by alexpott, joelpittet, ericjenkins, stefan.r, Wim Leers, Cottser: Remove all code usages SafeMarkup::checkPlain() and rely more on Twig autoescaping

Issue #1392754 by tss, justAChris, jhodgdon: Comply with new documentation standards for @file for namespaced class files

Issue #2457887 by prateekMehta, stefan.r, rpayanm, alexpott: Use Utility\SafeMarkup class instead of Utility\String for placeholder(), checkPlain(),format() functions

Issue #2267763 by pwolanin, tim.plunkett: Page titles with %placeholders are broken when used as breadcrumbs.

Issue #2076085 by dawehner, damiankloip, Letharion, pwolanin: Resolve the need for a 'title callback' using the route .